茄子果实采后软化过程中细胞壁组分及其降解酶活性的变化

Changes in Cell Wall Components and Cell Wall-degrading Enzyme Activities of Postharvest Eggplant Fruits During Softening

研究了细胞壁组分及其降解酶活性的变化与茄子果实采后软化的关系。结果表明,采后茄子果肉硬度随贮藏时间的延长而不断下降。贮藏期间果肉水溶性果胶(WSP)含量在贮藏前12天不断增加,之后快速下降,而共价结合型果胶(CSP)、半纤维素和纤维素等细胞壁组分含量持续减少。果肉果胶甲酯酶(PME)、多聚半乳糖醛酸酶(PG)和纤维素酶(CX)活性均呈先升高后下降趋势,分别在贮藏至第6、9、12天达到最大值;β-半乳糖苷酶(β-Gal)活性始终保持较高水平,且在整个贮藏期间活性变化不明显。相关性分析结果表明,CSP、半纤维素和纤维素的降解与采后茄子果实软化密切相关,PG和CX在茄子果实采后软化过程中起着重要的作用。

Changes in cell wall components and ceil wall-degrading enzyme activities of postharvest eggplant fruits during softening were investigated. The main results were as follows. Firmness of eggplant flesh constantly de- clined during storage. Water-soluble pectin （WSP） content continuously increased 12 days after storage, and followed by quickly decreasing. Covalent pectin （CSP） , semicellulose and cellulose contents decreased progressively. Pectin- methylesterase （PME） , polygalacturonase （PG） and cellulase （CX） activities firstly increased and then decreased, and respectively reached maximum when stored to 6, 9 and 12 days.β-Galactosidase （β-Gal） activity maintained at a high level and did not change obviously during storage. Analysis of correlation showed that the degradation of CSP, hemicellulose and cellulose was closely related to softening of postharvest eggplant fruit. PG and CX played an impor- tant role in the process of eggplant fruit softening.